The Research On The Process Of Edible Packing Membrane Made Of Radix Platycodonis Polysaccharide

This research concerns on the extraction process of the Radix platycodonis polysaccharide (RPP)assisted by microwave; the ingredients in masking technique based on the RPP, especially about the possible influence of each ingredient on the functions of the edible membrane, and further more, optimized the ingredients through the response surface used the performance parameter TS and FE as the indicator; optimized the process of masking technique by the same method; also the research on the inhibitory action of the three symbols to the common bacterium in food. The results are as follows:Optimizing the extraction of the RPP assisted by the microwave through the response surface. The dry rootstock of Radix platycodonis was used as the raw material, extracted the RPP assisted by the microwave. The factors which influenced the extraction rate of the RPP were:(ma:vb)>the time of the microwave>the microwave power. The most suitable condition is:microwave power 497W,3.6min by microwave,(ma:vb)41:1,the predicted value of the extraction rate of the RPP could be 29.18%, and actual value is 28.83%.Optimizing the ingredients of the RPP edible membrane. The content of polysaccharide, the sodium alginate and the glycerol could influence the mechanical behavior, barrier property and the aspect of the membrane on the certain level. The glycerol has an significant enhancement on the membrane's FE, excessive glycerol has attenuation on the membrane's TS. The TS and FE were chosen as the quantization indicator while the optimized ingredients as follows:The results used the TS as the response indicator:the factors influence the TS:the content of the sodium alginate>the content of the glycerol>the content of the RPP.The most suitable condition is:the content of the RPP 2.16%, the content of the sodium alginate 2.66%, the content of the glycerol 1.97%. The TS predicted value could be 8.174MPa, and the actual value is 7.875MPa.The results used the Fe as the response indicator:the factors influence the FE:the content of the glycerol>the content of the sodium alginate>the content of the RPP. The most suitable condition is:the content of the RPP 2.04%, the content of the sodium alginate 1.92%, the content of the glycerol 1.97%.The FE predicted value could be 170 double fold, and the actual value is 167 double fold.The optimizing of the RPP edible membrane's masking process. The pH of the casting solution, the stir speed, the deaeration time, the drying temperature were chosen as the indicator of the experiment of single factor to research on each factor's influence on the membrane's character. And then the TS and FE were chosen as the indicator of the response surface to obtain the best process of the membrane.The results of the experiment of single factor:pH 7.0, stir speed 180r/min, deaeration time 40min, the drying temperature 45℃.The results of the response surface used TS as the indicator:the factors influenced TS:the stir speed>the deaeration time>the drying temperature.The most suitable condition is:the stir speed 206r/min, the deaeration time 44min, the drying temperature 47℃.The TS predicted value could be 8.65MPa, and the actual value is 8.45MPa.The results of the response surface used FE as the indicator:the factors influenced FE:the deaeration time> the drying temperature>the stir speed. The most suitable condition is:the stir speed189r/min, the drying time 43min, the drying temperature 46℃.The FE predicted value could be 190 double fold, and the actual value is 187 double fold.The primary research on the RPP's bacteriostat fuctionThe results showed that:All the three symbols of RPP have the bacterostat function on the Bacillus coli, Staphylococcus aureus, Bacillus subtilis; and have no bacterostat on the B. licheniformis and Aspergillus niger. The effect of the bacterostat:Bacillus subtilis> Staphylococcus aureus>Bacillus subtilis. This result was considered to be significant and the high concentration symbols have better bacterostat than the lower ones.Generally speaking, the research has totally five response surface on the experiment of the RPP extraction, the ingredients' optimizing and the membrane's process. The results obtained in the experiments are all in the ideal scope and the bacterostat is also ideal. These results provide a strong theory and supporting data in the industrial production and practice of the RPP edible preservative film.